Air vents are employed to direct the flow of processed or vented air from a heating and air conditioning system to an area to be affected. In many situations, it is desirable that a human operator be capable of directing the air flow to a select location. By way of example, an air vent employed in a motor vehicle directs air flow from the dashboard or console of the motor vehicle to a location in the passenger compartment that requires processed air. To this end, one or more controls are provided that allow the driver or passenger to operate the air vent so as to direct the air flow to the desired location.
Because the primary purpose of the air vent is to direct the flow of processed air, it is desirable that the air vent exhibit good air flow directability. In other words, the air vent should effectively direct air flow in the direction intended by the operator. Moreover, air vents should be capable of controllably directing air in both the vertical and horizontal directions.
In addition to good air flow directability, air vents are preferably easy to control and adjust. For example, because a driver of a vehicle must concentrate on a number of other controls required to operate the vehicle, it is necessary that the air vent controls if the vehicle be intuitive and simple to operate so as not to distract the driver from the more important task of operating the vehicle.
Air vents employed in vehicles, as well as in other environments, also have a function as a styling element. In vehicles, air vents are prominently placed on the dashboard or console. Accordingly, the driver and passengers have an unobstructed view of the air vents. Therefore, it is important that the air vents are aesthetically pleasing to the driver and passengers of the vehicle. To create an aesthetically pleasing appearance, air vents are preferably integrated into the overall design of the passenger compartment of the vehicle. To this end, it is often desirable to at least partially conceal the inner components of the air vent from the driver and passengers to increase the aesthetic appeal of the air vent.
One common air vent configuration that attempts to address the above concerns is a barrel-type vent, such as the air vent is described by Mikowski in U.S. Pat. No. 5,690,550. A barrel-type vent includes a rotatable barrel and a set of rotating vanes. The barrel has a number of fixed parallel vanes which direct the air flow in accordance with the rotational position of the barrel. The set of rotating vanes are positioned behind the barrel, and each rotating vane is connected to the other rotating vanes by a link bar which links the rotating vanes to one another such that each vane rotates on its axes at the same rate as the other rotating vanes. A knob is used to rotate one of the rotating vanes, causing the link bar to slide back and forth, which in turn rotates each of the other rotating vanes about its respective axis.
One drawback of the barrel-type vent design is that the control and operation of the vent is not intuitive. To direct the airflow up and down, the barrel must be rotated relative to the dashboard whereas to direct airflow left and right, the knob is urged to slide the link bar relative to the barrel. As a result, two types of control actions, with two distinct types of tactile feedback, are used to perform the directional adjustment. Using such distinctly different control actions for a similar task makes directing air flow with this type of air vent non-intuitive.
Another drawback to the device disclosed in the Mikowski patent is that the set of rotating vanes is located behind the barrel. As a result, the air directing influence of the rear-located rotating vanes is diminished. In particular, any left or right air flow influence or direction occurs deep within the vent (due to the location of the vane set behind the barrel) and is therefore muted by counter air currents reflecting off of the sides of the vent before the air exits the vent into the passenger compartment. As a result, air flow is not directed to the intended portion of the passenger compartment with great effectiveness.
Still another drawback of the barrel-type vent is that the vertically rotating barrel is not aesthetically pleasing because multiple vents having barrels in different stages of rotation cause the dash to appear aesthetically unbalanced.
One proposed solution to the problem of using two types of control actions is to have two sets of rotating vanes controlled by a single control knob. A vent that incorporates a single control knob feature is disclosed in U.S. Pat. No. 5,480,350 to Naruse. The Naruse patent shows a first set of rotating vanes that is positioned in front of a second set of rotating vanes. The control knob rotates the first set of vanes about a first set of axes to direct the flow of air either upward or downwardly. An engagement portion of the control knob passes through the first set of vanes and is operable to cause the second set of vanes to rotate about a second set of axes positioned behind the first set of axes. This configuration allows the airflow to be directed left or right with the second set of vanes using a motion similar to the motion used to direct the airflow up and down with the first set of vanes.
While the controls in the device disclosed in Naruse are more intuitive than those associated with barrel-type vents, such controls nevertheless have drawbacks. For example, like the barrel-type vent designs, one vane set is located squarely behind the other vane set, in other words, deep within the vent. Accordingly, for the same reasons as those discussed above in connection with the Mikowski patent, such a configuration results in limited effectiveness of the air flow directability of the rear vane set.
Yet another solution to the problems associated with the barrel-type air vent is described by Stouffer in U.S. Pat. No. 5,356,336. This air vent configuration uses a joystick to move an open frame in a duct of the vent. The open frame has a number of vanes which are oriented in a substantially parallel manner. The joystick acts a single point controller and allows the driver or passenger to pivot the frame up, down, left and right about a ball joint. The ball joint provides the operator with substantially identical feed back in all directions, allowing intuitive operation of the vent. The frame directs the air that exits the vent in a direction parallel to the vanes. The Stouffer design also includes a grill which is operable to visually conceal the inner components of the vent from the driver and passengers.
However, one disadvantage of the Stouffer design is that the size of the frame that directs the air flow must be significantly smaller than the size of the duct in order to allow the frame to be positioned within the duct. Limiting the size of the frame limits the surface area of the vanes which is used to direct the air flow. By limiting the surface area of the vanes, a smaller portion of air that exits the air vent is effectively directed by the frame. As a result, the vent described in the Stouffer patent exhibits reduced effectiveness in air flow directability.
What is needed therefore is an apparatus and method for controlling the flow of air in a vent which has improved air directability combined with intuitive control action. A further need exists for such an apparatus to use a single point controller, such as a joystick, to direct both a first set of vanes and a second set of vanes. Still a further need exists for such an apparatus that provides at least partial concealment of the components of the apparatus.